Electropneumatic vent-valve device.



E. H. DEWSON (in W. V. TURNER. ELEGTROPNEUMATIO VENT VALVE DEVICE. APPLICATION FILED JUNE 21, 19 12.-

Patented Mar. 9, 1915.

WITNESSES TTTE and s EDWARD H. DEWSON, 015 NEW YORK, N. 5L, AND WALTER, V. TURNER, 0F EDGEWOOD, PENNSYLVANIA, ASSIGNORS TO THE WESTINGHOUSE AIR BRAKE COMPANY, OF WILMEREING, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

JELECTEUJPNJEUMATIC VENT-VALV1E DEVICE.

tpecification of l'iettere Patent. i

Patented Mar, 9, 1915.,

minimal application filed May a, 15910, Serial No. 560,172. Divided and this application filed June 21, 1912.

, aerial No. 705,074. I

To all whom it may concern Be it known that we, EDWARD H. Dawson and WALTER V. TURNER, citizens of the United States, residents of New York, in the county of New York and State of New York, and lEdgewood, in the county of Allegheny and State of Pennsylvania, respectively, have invented a certain new and useful limrovement in Electropneumatic Vent-Valve evices, of which the following is a specifination.

This invention relates to an electro-pneumatic brake apparatus and is a division of application ,Senal No. 560,172, filed May 9, .15 1910. -Y The principal object of our invention is to j'provi e an improved electro-pneumatic train pipe vent valve device;

lln the accompanying drawing Figure 1 is a central sectional vlew of the improvedelectro-pneumatic train pipe vent valve deviccembodying our invention and Ijig. 2 a diagrammatic view showing the WlIlIlg and piping connections for said vent valve de- According to the construction illustrated, the improved vent valve device may comprise a casing 30 having a piston chamber containing a piston 32,. the chamber 31 on one side of the piston being normally open to the tram pipe through a passage 33 con- :taining a check valve 34, and passage 35 leading to pipe 36, which is connected to the train pipe 1. The piston is subject on its 0 posite face to the pressure of a chamber 3? which is preferably connected through a passage 38 with a small reservoir 39, so as .to increase the volume of the chamber.

passe e 33 to chamber 31.; A passage 46 leads rom the chamber 31 to an electro-mag-.

tact 56. One fixed switch contact 59 is connected by a wire 57 with a train wire 58, the latter wire bein connected to one terminal of the vent va ve magnet 52, and the .other fixed contact 60 is connected to ground, so that when the switch is closed the line wire 58 and the magnets 52 are grounded. A spring 61 acts on the piston 54 to normally maintain the switch open. The other terminal of the magnet 52 is connected by a wire 62 to a source of current, such as the third rail or trolle preferably on each car, a suitable resistance 64 being interposed in the circuit.

When the brake system is charged up, fluid under pressure flows through the passage 35 and a small .port 68 in the check valve 34 to passage 33 and thence to chamber 31, and the piston 32 being in its outer position, air flows through a feed groove 65 around the piston, charging the chamber 37 and reservoir 39 to the normal pressure carried in the system. The circuit of the magnet 52. is normally open and the valve 48 is held closed by the spring 50, but upon closing the circuit, the movement of the armature 51 opens the valve 48 and air is vented from chamber 31 through passage 46 to exhaust port 49. The higher pressure in chamber 37 thereupon shifts the piston 32 to its inner seat opening the valve 41. Fluid from the train pipe then flows through passages 35 and 42 to chamber 43 of the switch de vice 44 and thence through a assage 66 to the upper side of piston 54. aid piston is thus shifted to cause the switch contact 56 to close the circuit across the terminals 59 the feed groove face of piston 45, then the piston 45' moves from its upper seat, and exposing the full and 60, so that the train wire 58 is grounded and all the magnets 52 arethereupon energized.. In the closed position of the piston 54, a port 67 is open to the space above the piston, so that fluid from the train pipe can esca e to an atmospheric exhaust port 68.

pon a predetermined reduction in train pipe pressure by venting to the exhaust port 68, the spring plshifts the piston 54 upwardly, opening the circuit across the terminals closed, and as the piston 32 is seated, with 65 closed, fluidprssure is bottled up in chamber 37. The pressure on the opposite side of piston 32 continues to reduce by flow from chamber 31 past check valve 34 to vent passage 42, an exhaust port 99 opening to passage 66 providing for the release ofair when the port 68 is cut ofi, until the pressure in the chamber 37 acting on a diiferent'ial' area 69 of the piston'45, communication being provided to said area by way of ports 70, together with the train pipe pressure actin of said piston 45, 1s sufiicient to overcome thetrain pipe pressure acting on the outer area thereof to the higher pressure of the chamber 37, is instantly seated downwardly, so as to cut off communication from the train pipe passage'33 to chamber 31. It will be noted that a restricted passage- 71 is provided through the stem 72 of the piston 32, so that the pressure of fluid flowing from the passage 35 to the passage 42 is supplied to the chamber within the piston 45. The piston being seated downwardly, communication is opened from chamber 37 through ports 70 and the restricted port 71 to passage 42, so that the pressure in chamber 37 now reduces with the train pipe pressure, while the pressure in chamber 31 is bottled up. It will there fore be evident that as soon as the pressure in chamber 37 reduces a certain amount, the pressure in chamber 31 will exceed the -pressure in: chamber 37 and the piston32 will thereupon be shifted upwardly to close the valve 41, and out off the further'flow of air from the train pipe. The pressure-in the chamber within piston 45 then rapidly drops to atmospheric pressure by flow through the passage 42 and exhaust port 99, and the pressure acting on the lower exposed face of the piston 45 thereupon shifts the piston to its upper seat. 7

It will now be evident thatthe vent valve device operates to eifect a predetermined reduction in train pipe pressure, the reduction depending upon the relative proportioning of the parts, .so that all the triple valves in the train are caused to operate practically simultaneously to produce an 59 and 60. The magnets 52 being thereupon deenergized, the valves 48 are within the seated areacar,

emergency application of the brakes. One of the important features of our invention is that the simultaneous action of all the vent valves in the train may be effected by the-action of any one vent valve pneumativ;

cally, as by a sudden reduction in train pipe ressure initiated at some point in the train,

or example upon a break-in-two, or upon making an emergency reduction in train pipe. pressure at the head end of the train valves are caused to operate simultaneously. 4 The circuit of the magnets 52 may be closed in various ways, as by means of a 'conductors switch 73 on the-car, adapted to connect the line wire58 to round, or by providing a contact in the rake switch adapted in emergency position to connect the-wire 58 to ground.

- As an additional safeguard, means may be provided in some cases, whereby the vent valve is operated by the breaking of a normally closed circuit, for example, a magnet 75 having an armature 7 6 for controlling a valve 77 may have a pipe connection 78 tothe'passage 46, the opening of the valve 77 being adapted to vent air from passage 46 and chamber 31 to an exhaust port 79. The circuit for magnet 75 is preferably arranged with a wire 80 on the head car connected to a source of current and one terminal of the magnet 75 and a wire 81 connected to the other terminal and extending through the train and including the magnets 75- on the other cars of the train. On the last carjthe wire 81 is connected to the ground. It is thus seen that the magnets 75 are maintained normally energized and the v valves 7 7'are' kept closed by the armature 76. If the wire 81 is broken from any cause, or

if there is a failure of current, the magnets 75 are operated and air is vented from the *vent valve pistons 32 to effect a sudden reduction in train pipe pressure and an emergency application of the brakes;

, Instead of an additional contact in the brake switch, the action of the vent valves may be initiated by connecting the usual exhaust pipe of the brake valve with the chamber 43 of the vent valve switch on the head so that in emergency position air exhausted from the train pipe is vented to chamber 43 and thereby the-switch 56 on the head car is actuated to ground the vent valve circuit for the train and in this manner effect the simultaneous action of all the vent valves.

If the switch 44 is connected to the exman-ate haust pipe of the brake valve, the exhaust of air from the train pipe in makin' service applications of the b by the port 99, which is made of sulficient size for that purpose. Thus the piston 54 will only be actuated when a sudden reduction in train pipe pressure is made.

Having now described our invention, what we claim as new and desire to secure by Letters Patent, is

1. In a fluid pressure brake, the combination with a tram pipe and a valve device for application of the brakes, of

controlling the a pneumatically operated valve mechanism adapted to efl'ect a reduction in train pipe pressure and electrically controlled means for also operating said valve mechanism. fluid pressure brake, the combination with a brake cylinder, train pipe, and,

means operating upon a reduction in train application of he combination with an automatic brake apparatus operating upon a in train pipe plication of the brakes,

electrically controlled. means for efl'ectmg t e operation of said vent valve mechanism,

the electric circuit ofsaid electrically controlled means. f "2 6 f:

4. In a fluid pressure brake, the combination with a train pipe and brake cylinder, of a vent valve mechanism for locally ventingthe train trolled device for effecting the operation of an electric switch device operated by the vent valve mechanism, an electric circuit for said electrically controlled device, and an electric switch governed by the vent valve mech cuit. 5. In a fluid pressure brake, the combina-. tion with a train pipe, of a vent valve mech-v anism having a movable abutment normally subject to opposing fluid pressures, one of which is train pipe pressure, and electric means for venting fluid from one side of said abutment to operate anism and produce train pipe.

6. In a fluid anism for controlling said electric cira local venting of the anism adapted upon a sudden reduction in train pipe pressure to eflect a local venting of the trainpipe, electric means for also operating said vent-valve mechanism, and

vent. valve mechanism upon venting the train rakes is provided for the train a electric switch tion with a brake cylinder,

nation .with a mechanism co reduction pressure for effecting an apof a vent valve mechanism adapted to locally vent the train d I ,sai

pipe, having an electrically con-- said vent valve mecha tion in train pressure brake, the combina-' tion with a train pipe, of a vent valve mech-' said.

.nation with a pipe to close the circuit for said electric means.

7. In a fluid pressure brake, the combination witha train pipe, of a vent valve mechanism operating upon a sudden reduction in train pipe pressure for locally venting electric means for also operating said vent valve mechanism, and an device operated by the flow of air from the vent valve mechanism upon venting. the train pipe for controlling the of said electric means.

electric circuit pressure brake,

lve means and an electric switch device for controlling the electric circuit of said electrically controlled means and operating upon an emergency application of the brakes to efl'ect the operation of said electrically controlled means.

In a fluid pressure brake, the combitrain pipe, of a t ereby for releasing in venting the train 10. In a fluid pressure brake, the combination with a train mechanism adapted to locally vent the train pipe and electrically controlled means adapted either upon opening or closing of an electric circuit to effect the operation of said vent valve mechanism.

11. In a fluid pressure brake, the combination with a train pipe, of a vent valve mechanism for eflecting alocal venting of the train pipe, electrically controlled means op erating upon energization and electrically controlled means zation for operating said vent valve mechanism.

12. In a fluid pressure brake, nation with a train pipe, mechanism operating upon of a vent valve a sudden reducpipe pressure for effecting a localventing of the train pipe, and electrically controlled means operating either upon the completion of one electric circuit or the breaking of another electric circuit for also eflecting the operation of said vent valve mechanism.

13. In a fluid pressure brake,

brake cylinder,

the I combitrain pipe,

pipe, of a vent valve operating upon denergithe combiand triple valve device operating upon a sudden reduction in train pipe pressure for eifecting an emergency application of the brakes, of a valve device adapted upon a sudden reduction in train pipe pressure to effect a local venting of the train pipe, an electrically controlled means for operating said vent valve device, and an electric switch operatmg upon a sudden reduction 1n train pipe pressure forcontrolling the circuit of 10 said electrically controlled means.

In testimony whereof we have hereunto set our hands.

' EDWARD H. DEWSON.

WALTER V. TURNER. Witnesses: A. M. CLEMENTS,

- S. W. KEEFER. 

